Traditionally, in a telecommunications network, users' or customers' premises are connected to a Public Switched Telephone Network (PSTN) by a lead-in cable consisting of either one or two pairs of copper conductors (wires). The lead-in cable is routed to a dwelling or other premises either aerially, in the case of an aerial Customer Access Network (CAN), or underground for the more recently deployed underground CANs.
Generally, new estates and residential developments, at least in Australia, now deploy cable underground. The cable is routed from a distribution point near a property boundary via a small plastic conduit to an entry point to a dwelling. The entry point is typically located at a convenient position, such as close to the electrical cable entry (meter box) or at some other point where access to the building is relatively straightforward.
The lead-in cable is generally pulled through the conduit, which typically has an internal diameter of 20 mm, by means of a thin cord. The cord is threaded through the conduit by first pushing a rigid rod through each 4.5 m length of conduit (rodding process) With the rope attached at one end. Having performed the rodding process it is then a simple matter to tie the rope to the end of the lead-in cable by means of a knot and then use the rope to haul the cable into and through the conduit. Most often the conduit does not form a completely straight line, but typically undulates and bends with a number of bend elements often being permitted with a radius of curvature down to about 100 mm.
There is an emerging need to replace copper conductor lead-in cable with fibre optic lead-in cable to provide users or customers with a range of new or improved services, such as Video on Demand (VoD), high speed Internet access, as well as telephone services over a single integrated network.
In the case of copper lead-in cable, the connection to the customer's equipment, whether the equipment is a standard telephone or a Digital Subscriber Line (DSL) modem, is straightforward and easily accomplished in the field with simple hand tools. The process may involve fitting a connector with screw terminals or, more likely, fitting a connector that can be secured by means of a simple hand operated crimping tool similar to a pair of pliers.
With the move to fibre optic systems the whole process becomes potentially far more complicated. While the fibre optic cable, and in particular the fibre, is very flexible the fibre optic cable cannot be tied to a hauling rope without fracturing the fibre or, at best, severely affecting the fibre's transmission characteristics. The connection to the Optical Network Unit (ONT) that effectively forms the interface from the new generation PSTN and the customer's equipment requires a fibre to fibre connection to be made.
The fibre used in these systems is typically singlemode which has a mode field diameter (the part of the fibre that carries the signal) of 9 microns. To obtain a good and reliable transmission it is necessary to butt two fibres together with sufficient precision such that the two extremely small mode fields align exactly. This process is typically accomplished in one of two ways. A direct fusion splice may be used whereby the two fibre ends are mounted in a complicated, high precision, fusion splicing machine that, using an electric arc, melts the two fibre end faces and fuses them together as one. Alternatively, a precision optical connector can be mounted on the end of each fibre and simply plugged together. Based on presently known technology, it is expensive and complicated, to fit a connector to a fibre optic cable in the field since the mating components of the connector have to be machined after fitting to the fibre to assure perfect alignment. Further, the end face of the connector has to be polished to minimise losses.
Some forms of cable hauling attachments are presently known. An electrical cable attachment made by Clipsal™ is designed for pulling electrical cables through conduits. These electrical cable attachments attach to the electrical cable by means of a rubber ring that is compressed onto the outer sheath of the cable by a conical gland nut. These devices are not suitable for use with fibre optic cable for at least the following reasons: (i) the outer diameter is large and would not fit through a 20 mm conduit commonly used in communication cable lead-ins; (ii) the device transfers the pulling load to the outer sheath rather than a strengthening element; (iii) there is no convenient way to house, seal and protect an optical connector.
A fibre optic cable pulling eye made by Poulen™ is commonly used for attaching hauling cord to fibre optic cables that are hauled into underground ducts. The device attaches to the cable either by the use of set screws that grip a central Glass Reinforced Plastic (GRP) element. Alternatively, the device grips onto a peripheral aramid strength member by crimping an outer sleeve down onto the cable. This device is problematic for at least the following reasons: (i) the device is very large and is designed for traditional multi loose tube configuration cables; (ii) in some fibre optic cables, for example cables for use in many residential CANs, there is no central strength element to be gripped; (iii) the crimp method of securing the eye is inappropriate in the necessarily small diameter of many conduits as the device is too large; (iv) there is no facility to protect a connector from the ingress of dirt and water.
Thus, there is a need for a relatively quick, simple and low cost installation of fibre optic lead-in cables to facilitate user or customer connections to new generation CANs. Many problems arise in seeking to deploy fibre optic lead-in cables using existing technology, these problems include:    (i) Presently known optical lead-in cables do not lend themselves to traditional installation methods since they cannot be hauled in the conventional way.    (ii) Connection of the optical lead-in cable to the ONT is relatively complicated.    (iii) The use of fusion splicing to connect to the ONT requires highly trained operators with complicated and expensive equipment that is not easily portable to the various locations where the splice is required.    (iv) It is not easily possible to fit optical connectors with the required level of performance in the field.    (v) The conduit from the distribution point to a customer's premises is small, normally being only 20 mm in diameter. The conduit is not straight in most installations.    (vi) A conventional fibre optic connector will not fit through a 20 mm conduit.    (vii) The development of a new estate is typically ad hoc in that once the sub-divisions are approved the infrastructure services are then installed. This typically means that electricity, water, gas and telecommunications services are pre-installed along the streets. At the time of installation it is required to pre-provision for each customer's requirements. There may then be anything up to perhaps 2-3 years before a customer's dwelling is built. This means that it is therefore necessary to be able to protect the fibre optic lead-in cable, and in particular the fibre end with a factory, or pre-fitted, connector attached, for at least this period of time from water (pits usually become flooded) and dirt (the working part of the fibre is only 9 microns in diameter).
This identifies a need for a system, device, fibre optic cable and/or method for facilitating the hauling or pulling of a fibre optic cable along a conduit, pipe or the like which overcomes or at least ameliorates some or all of the problems inherent in the prior art.
The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge.